Calculators for people who run infrastructure
Sizing backups, planning subnets, dimensioning clusters. The arithmetic sysadmins do on whiteboards and napkins, turned into precise, shareable tools. Everything runs in your browser; the numbers you type never leave your machine, and nothing sits behind a paywall.
Backup retention & sizing calculator
Model GFS retention against data growth, change rate and deduplication engine, global, per-copy or raw, and get 1/3/5-year capacity projections with CSV export.
Open → Tool 02 · NetworkingSubnet calculator
Network, broadcast, host range, netmask and wildcard for any IPv4 CIDR. With the binary laid out bit by bit, plus VLSM splitting into smaller subnets.
Open → Tool 03 · StorageRAID & ZFS capacity calculator
Usable capacity, efficiency, fault tolerance and URE rebuild risk for RAID 0/1/5/6/10 and RAIDZ1/2/3. With a comparison of every layout on your drives.
Open → Tool 04 · Backup & NetworkingBackup window & bandwidth calculator
Transfer time for any data size on any link, with realistic utilization, and the bandwidth you need to fit a backup window. 100 Mbps to 100 GbE compared.
Open → Tool 05 · KubernetesKubernetes cluster sizing calculator
Nodes needed from pod requests, system reserves, pod-per-node limits and N+1 failover. With a comparison across node shapes.
Open → Tool 06 · VirtualizationVM consolidation & overcommit calculator
Hosts needed for your VM fleet at any vCPU:core ratio, RAM-honest, with N+1 failover and a guide to which ratio suits which workload.
Open → Tool 07 · Cloud & InfrastructureCloud vs on-premise cost calculator
Monthly and 5-year TCO with every rate editable. Compute, storage, egress vs capex, power, colo and support. No vendor propaganda.
Open → Tool 08 · StorageCeph capacity calculator
Usable space for replicated and erasure-coded pools, with full ratio and self-heal headroom. What the cluster can really store, not the raw number.
Open →Why these tools exist
Vendor sizers are marketing funnels, spreadsheets get lost, and most online calculators were last touched in 2010. These are built by a working backup and infrastructure engineer, model the math honestly, including where it's an approximation, and every result is a shareable URL you can drop in a ticket, a design doc or a forum answer.